Roman coins link Pembrokeshire fort to ancient Welsh legend
New Roman coins found near Frenni Fawr give fresh weight to the Macsen Wledig legend, reshaping understanding of Roman activity in west Wales.
Two late‑fourth‑century Roman coins unearthed near Frenni Fawr have given a material edge to the centuries‑old Welsh tale of an emperor’s camp in Pembrokeshire.
The coins were recovered during the latest phase of work at a Roman fort first identified in 2024 by Dr Mark Merrony, a Pembrokeshire‑born archaeologist specialising in Roman Britain and affiliated with the University of Oxford.
Excavations this season have also revealed a range of artefacts, including Roman pottery, building tiles, an iron writing stylus, compacted floor surfaces and wagon ruts, all pointing to a substantial military presence.
A geophysical survey has mapped the outlines of several large buildings within the enclosure, confirming the site’s characteristic rounded‑corner plan typical of an auxiliary fort.
The fort measures roughly 180 metres by 150 metres and is thought to have accommodated around 500 troops, according to the research team.
It lies about 3.5 kilometres south‑west of the summit of Frenni Fawr, a location that has been kept confidential to deter unauthorised searching.
The discovery of the two coins, dated to the late fourth century, raises fresh questions about activity at the site towards the end of Roman rule in Britain, although coins alone cannot determine how long a garrison remained.
What makes the find particularly intriguing is its possible link to Magnus Maximus, the fourth‑century Roman commander remembered in Welsh tradition as Macsen Wledig.
Maximus was proclaimed emperor by his troops in Britain in AD 383, later ruled parts of the European mainland and died in 388 after a failed campaign.
In the medieval Welsh tale “The Dream of Macsen Wledig”, part of the Mabinogion collection, the emperor is associated with a military encampment at Frenni Fawr.
Until now the story’s connection with the landscape rested on literary tradition rather than identified Roman remains nearby.
The fort and the newly recovered coins bring those two strands of history closer together, though they do not prove that Maximus ever set foot on the site or that the coins were deposited during his campaigns.
The legend was written down centuries after the events it purports to describe, meaning any direct correlation remains speculative.
Beyond the Macsen link, the excavation is reshaping the map of Roman west Wales, an area once thought to be peripheral to the main centres of occupation.
Evidence of substantial military buildings, a road layout and everyday objects is helping scholars build a more detailed picture of Roman activity in the Preseli Hills.
The find adds to the local archaeological narrative already shaped by the Roman fort at Wiston and ongoing research into possible Roman routes across Pembrokeshire.
Dr Merrony has previously argued that the county’s Roman military and civilian presence has been underestimated, a view now reinforced by the new material.
The research is slated for publication in the archaeology journal Antiqvvs, where further analysis will aim to clarify the sequence of occupation and the significance of the late‑fourth‑century artefacts.
For Pembrokeshire, the most compelling point may be that a story preserved for generations in Welsh literature can now be examined alongside physical evidence from the very landscape it describes, even if the final answer to the emperor’s whereabouts remains elusive.